Thursday, 14 October 2010

MRCP revision battle 29.2: Thyroid eye disease

Thyroid eye disease, referred to by its friends as 'TED', can occur in people who are hyperthyroid, hypothyroid or euthyroid.

Thyrotoxicosis from any cause can cause lid lag and lid retraction.

However, only Graves disease causes:
  • periorbital oedema
  • conjunctivial injection
  • proptosis/exophthalmos
  • opthalmoplegia/diplopia
  • papilloedema

(as an aside, I've always been mystified by the difference between proptosis and exophthalmos.  Unfortunately it appears I'm not the only one as some sources suggest the difference is related to the degree of protrusion whilst others say exophthalmos is used if the aetiology is endocrine and proptosis is used if the aetiology is not endocrine...)

25-50% of patients with Grave's disease have TED.

Risk of TED is increased in smokers.

The danger of TED is optic nerve compression.  Symptoms/signs of optic nerve compression include:
  • blurred vision/decrease VA
  • decreased colour vision
  • a relative afferent papillary defect

Treatment for TED is topical lubricants, steroids if severe and possibly even surgery.

Now for a horrid battle with hyperlipidaemia...